Stephen Dwyer believed that in his junior year at Mesa's Dobson High School, he would make a breakthrough in swimming and qualify for the Arizona state championships.

He took his training to a new level with Mesa Aquatics Club, and when the Arena Grand Prix came to Mesa in April, he studied Olympic swimmers such as Michael Phelps, Ryan Lochte and Conor Dwyer — to whom Stephen is not related but feels a kinship — to learn from their form.

Then in June everything changed. Dwyer was feeling tired, running a low-grade fever and complaining about bloating. Blood tests revealed a low blood-platelet count. Doctors found his spleen and liver to be enlarged.

The eventual diagnosis was acute lymphoblastic leukemia, a cancer that crowds out bone marrow and prevents the production of healthy blood cells.

Instead of the swimming that the 16-year-old expected to be doing this summer, Dwyer began weekly chemotherapy treatment June 17, strengthened by the prospect of a 90 percent cure rate.

A subsequent genetic test revealed that Dwyer's leukemia cells have fewer chromosomes than normal. The condition, known as hypodiploidy, significantly reduces the cure rate to 30 percent without a bone-marrow transplant.

"His older sister and younger brother were not (transplant) matches," Stephen's father, Rick, said. "Now we're looking in the general registry. They've found six or seven they're looking into further. It could happen as soon as next month."

Said Dwyer: "There are days where you are kind of bummed. It's easier if you have a positive mind-set. I like to be around people, because it takes my mind off it. It's nice to not always think about it."

But since last week, Dwyer has had little time to think about anything other than swimming.

Thanks to USA Swimming, he and his family have spent recent days at the National Championships in Irvine, Calif., watching hundreds of top swimmers vie for U.S. titles and spots on Team USA's roster for international competition.

The organization arranged for them to attend, paying for hotel accommodations and VIP tickets.

"We didn't tell him until Wednesday night because we didn't want to get his hopes up," Rick said, in case Stephen's white-blood-cell count was too low after treatment Tuesday at Phoenix Children's Hospital. But afterward, "he was doing pretty good, so we made the call to go, and here we are.

"They're treating him like a star. Everyone is rolling out the red carpet."

The Dwyers stayed at nationals through Sunday, the event's last day. Stephen met and had photos taken with swim stars Phelps, Lochte, Katie Ledecky, Aaron Peirsol, Dara Torres and Rowdy Gaines.

Best of all for the teen, he spent a few hours with Conor Dwyer and his family.

"I wasn't sure what to expect at first," Stephen said. "My mom is from Chicago (like Conor). Ever since London (Olympics), we've joked about our name connection. He sent me a bunch of caps and a T-shirt a month ago. I'm a big fan of his."

That feeling is mutual.

"What he is going through is much harder than what we do," Conor said. "He's a role model and a fighter. The kid's got a huge heart. We talked about swimming and how he's getting ready for his big battle.

"It puts swimming into perspective. What we do is fun. What Stephen is doing is truly remarkable. How he's handling it with such a positive attitude blows my mind and makes me want to do better with my attitude."

Conor, who was an Olympic relay gold medalist in 2012, proudly wears his DwyerStrong shirt from Stephen, knowing how much more it represents than his path to qualifying for a second Olympics.

The Dwyers live in Gilbert, although Stephen attends Dobson in Mesa, just as his mother did. He couldn't start school last week because of infection risks tied to blood-cell abnormalities.

Instead, Stephen will work online from home. He can swim only in his backyard pool.

Rick Dwyer remembers Stephen saying, soon after his diagnosis, that he always prayed to be someone who could change people's lives and that maybe this is the way.

"It's hard for us as parents not to follow along," Rick said. "We feel we're supposed to serve other people through this somehow."

That "somehow" may be educating others about bone-marrow donations, Rick said. He encouraged people to visit bethematch.org to learn more.

"Stephen is handling it with such grace," Rick said. "He's doing better than all of us mentally and psychologically."

"I'm excited to get back to swimming and see what I'll be able to do," Stephen said.